Well there are also rumours talking the existing 16 SU27/SU30 will be converted to all 16 SU30 MK2..at this moment if not mistaken only 9 from 16 are SU30 MK2..the other 3 SU27 SKM, 2 SU 27SK and 2 SU30MK..
I think perhaps those 4 original 1st batch order (2 Su27 and 2 Su30) that might be tonnyc heard rumours they are not in really suitable conditions for further upgrades.
Again is rumours only..However it's logical if 1 sq of F5 being replaced by SU35, then the other existing sq being converted to all SU30MK2..
But then again of planned 10 combat sq, TNI AU only have 8..with:
1 sq of F5 (being talked but not contracted yet with SU35)
1sq of hybrid Su27 and Su30 (being rumoured to be full Su30MK2),
2 sq of F-16 A/B/C/D..(being planned for all falcon star standard with blk 50+Avionics),
1sq of T/A 50,
1sq of Super Tucano as COIN,
2 sq of Hawk 100/200,
Plus with planned 2 new combat sq.
Those 2 Hawk, and 2 New combat sq is really what, LM, Sukhoi, SAAB, and Eurofighter aiming for..not just the F5 replacement..Especially with KFX/IFX project now being reviewed for Indonesian participation on the program by Jokowi's administration.
But then again..this is Indonesia and more importantly this is Jokowi's adminstration..an administration which not yet 1 year but full with inconsistant policy changes track record..so anything still can happen..